1. Field of the Present Invention
The present invention relates to the field of microprocessors and in particular relates to the organization of microprocessors as that organization limits or relates to the use and structure of microprocessor instructions.
2. Description of the Prior Art
Since their inception, digital computers have continuously become more efficient, expanding into new applications with each major technological improvement. The advent of minicomputers allow digital computers to be included as a permanent part of various process control systems. Unfortunately, the size and cost of minicomputers in dedicated applications has limited their use. Capacity and ability of such dedicated microprocessors has been due in part to a fixed or limited word length upon which the operation of the microprocessor is based.
Thus, prior art microprocessors typically assumed a certain memory structure or by reason of their internal organization were subject to certain limitations with respect to the manner and means in which digital information could be stored and retrieved from a memory and later manipulated within the microprocessor itself. These limitations led to restrictions as to how multiple byte words were to be stored within a memory with respect to word length boundaries, and restrictions as to the structure of instructions which were decoded in the microprocessor to manipulate the digital information. As a result, instruction sets for microprocessors necessarily were limited in the power of the instruction, and in the number of instructions which could be accommodated. Typically, prior art microprocessors, by virtue of their architectural organization, would require a large number of distinct instructions or comparatively complex instructions in order to perform relatively simple tasks.
The present invention, as disclosed herein, overcomes each of these disadvantages in the manner and by the means as set forth in the following brief summary.